Excavating machine



Se t. 11, 1934. L. M. ATKINSON 1,973,136

' EXCAVATING MACHINE I Filed. Dec. 10, 1932 2 Sheets-Sheet 1 INVENTOR L.ewi s IYLAl'kins an BY Z M ATTORNEYS.

Sept. 11,1934. L M. so 1,973,136

EXCAVATING MACHINE Filed Dec. 10, 1932 2 Sheets-Sh 2 FIG. 6,

2'4 .0 a 2 49 A d Q 45 a o a U. n L 5 22 46, I

K (7 Z7 44 J 34 gm 'LLL'F :46 21s /2 ,1 Q Q I I. /4' 28 PM I FIG T 0 fl[Q] xv INVENTOR.

L. Ewis M.A1Ikins an Y mechanism Patented Sept. 11, 1934 paired s rEXGAVATING MACHINE IzeWisllLiAtkinson, Pittsburg, K'ans.; C. 0; Davisadministrator oi said' Lewis M. Atkinson, de-

Application: Deceinben-lO, 1932, Serial No. 646,695, 'YClaims: (01.214-1 5) The present invention relates to: excavating use as a part oflarge revolving shovels, such as coal-stripping shovels; and shovel'siorthe strip-'- ping and loading of ores, it is not limited to such use; itmay be applied to the smaller excavatingmachines where the load or workis gathered by the use of a dipper, scoop, or similar unit adapted topenetrate the mass laterally in c'ontr'adistinc- 1 tion to clam shellbuckets which penetrate the mass by a direct fall or substantiallyvertical downward movement.

The principal" object of the invention is-to-pro vide mechanismassociated with theloadhoisting to counteract the weight of, or theforce of gravity acting upon thee'xcavating mem her and accessories, andin some instances theload of material carried by the excavating member,so as to increase the efliciency and stability, 1 and reduce the expenseof operation of the equipment.

Another objectof the invention is to .providecounteracting mechanismassociated with the. load hoisting mechanism so as toreduce the horse25. power required by the prime movers, such as.

or internal combustion engines, or electric. motors to operate theexcavator; thereby increasing the dirt moving capacity of the excavatorequipped with the present invention by utilizingpower now lost inhoisting'and. l'oweri'ngthe excavating member and accessories. of theexcavating machine are heavier than the load to be lifted and by themeof the counteracting mechanism, the eniciency and capacity of theexcavating machine are materially increased.

Another object of the invention is to. utilize a. vertically guidedweight, preferably of a variable nature, much heavier than'the parts ofvtheload" hoisting mechanism which it is to counteract, and by the use ofmotion transmitting and speed reducing mechanism operatively connectedwith" the weight and load hoisting mechanism, provide optimumcounteraction with but short lineal travel of the weight as comparedwith the lineal travel of the excavating member. This makes. possiblerelatively short guides for the weight, reducing the cost of manufactureand increasing stability of the structure on its base.

A further object of the invention is to provide means for adjusting theposition of the weight in guide, independently of movement'of the;excavating member. This is particularly advan-- tageous where theexcavating machine is equipped. with a boom capable of being raised andlowered and where such change. in position of the boom These parts!effects the motion transmitting and speed reduc-' ing' mechanism betweenthe load hoisting mechanism andthe weight. Such adjusting means alsomakes possible the use of relatively short guides forthe weight since,by adjustment, its path of travel or amplitude'oi movement may bemaintained substantially the same during a load engaging and liftingoperation even tho the position or the boom be changed by raising orlower ing same as required, according to the conditions metduring-different excavating operations. The adjusting means alsoenablesthe operator totake up stretch in the cables, which may form a part ofthe hoisting mechanism and the motion transmitting and speed reducingmechanism, which cables are lengthened as a result of normal wear. In apractical example, the motion transmitting and-speed reducing mechanismmay be pluralpart tackle and by suspending the weight through. J

two of such and utilizing the adjusting means for each, the: weight maybe suspended plumb in its guide instead of sagging on either side asaresult of one weight supporting cable wearing faster,

and hencelengtheningto-a. greater degree, than thecableon the oppositeside of the weight.

Another object of the invention is to provide counteracting mechanismwhich will serve its: purposeas hereinbefore set forth and also aid inmaintaining the stability of themachine, thereby avoiding the use ofheavy ballast weight, now commonly used at the rear of the excavator cabopposite to the end supporting the boom, and which ballast, as nowcommonly used, serves but one purpose,to offset the weight of the massat the opposite side of the center of gravity of the machine. v

A, further object of the invention is to provide counteracting mechanismwhich may be appliedto the conventional or now commonly used excavatingmachine without considerable change or replacement of parts.

Otherobjects and advantages of the invention willappear in the followingdetailed description' taken in, connection with the accompanyingdrawings, forming a part of this specification, and in whichdrawings:---

- Figure 1 is a view partly in elevation and partly in vertical sectionshowing an excavating machine equipped with one form of the presentinvention.

Figure 2 is a fragmentary view in plan, with parts broken away to showdetails.

Figure 3 is an end elevation of the machine, same having, been swung onits base thru an arc of ninety degrees from the position shown in Figure1.

Figure 4 is a View on an enlarged scale, partly in elevation and partlyin vertical section, show ing the weight, a portion of the motiontransmitting and speed reducing mechanism, and means for adjusting thelatter so as to maintain the same path of travel for the weight,regardless of the position of the boom.

Figure 5 is a detail view in elevation showing a modification or suchadjusting means.

Figure 6 is a view similar to Figure 1 showing a modification or" theinvention, and particularly well adapted for use as an addition toconventional or now commonly used excavating machine.

Figure 7 is a view similar to Figure 2 but show-,

ing the'modification as disclosed in Figure 6.

In the drawings, wherein similar characters designate similar or likeparts throughout the several views, A designates a carriage of theexcavating machine; B the revolving frame mounted thereon; C loadcollecting and hoisting mechanism on frame B and comprising a boom D,boom hoist E, load engaging unit or excavating member F, boom machineryG and excavator hoistI-I; and J counteracting mechanism associated withthe load collecting and hoisting mechanism C, and comprising a weight K,a support and guide L for the weight, motion transmitting and speedreducing mechanism M, and means N for adjusting the motion transmittingand speed reducing mechanism to change the relative position of, theweight K in itsguide, independently of movement of the load engagingunit.

In the example shown, the carriage A comprises a base 8, supported bytrucks 9. s

The frame B may be revolubly mounted upon ;that the inventionmay beapplied to other types of excavating machines and perhaps its onlylimitation that it is not applicable to excavating machines using clamshell buckets intended to penetrate the mass to be lifted, by directfall, or a substantially vertical downward movement. The boom D ispivotally connected at its foot 12 to the end 10 of frame B, by brackets13, a pivot pin 14 or other suitable assembly permitting the boom to beswung upwardly and downwardly by use of the boom hoist E. The boom isprovided with a sheave 15 at its point for cooperation with theexcavator hoist H. The load engaging unit' or excavating member Fcomprises a dipper 16 and a dipper handle 17, the latter being'providedwith a rack 18 for cooperation with the boom machinery G. Suchmachinery, in the example shown, comprises a shipper shaft 19 having apinion 2O thereon for meshing relation with the rack 18, the shippershaft 19 beingrotated J through gear 21 thereon, meshing with a pinion22 on the shaft of motor 23. By this boominachinery, the excavatingmember F may be proiected and retracted with respect to the boom in theusual manner. p

In the example shown, the'boom hoist E comprises four-part tackle 24associated with a drum 25, operated in any suitable manner, such as bymechanism including worm 26 and worm wheel 2'7.

The excavator hoist H, in the example shown, comprises a drum 28,rotated by a gear 29, meshing with a pinion 30 on the shaft 31 of primemovers 32, and suitable tackle 33 connecting the excavating member Fwiththe drum. In the example shown, the prime movers 32 are electric motors,suitable current being supplied thereto through motor-generator set 34.As a typical example, the drum 28 may be of the type provided withoppositely running grooves, start ing at the center, so that two linesor cables are operatively connected to the drum, and to the dipper bail36, the cables 35 running over boom point sheaves 15 in the usual way.

Concerning the counteracting mechanism J as shown in Figures 1-5, theweight K is preferably in the form of a large receptacle 37 containing aquantity of material 38 of considerable weight, such as fragments ofmetal. The effective weight of the unit may therefore be varied byadding material to, or removing material from the receptacle 37. Thusoptimum counteraction, utilizing the weight, may be had by experimentand observation of the equipment in operation. The weight 3'? ispreferably provided with oppositely disposed grooves 39 for cooperationwith rails 40 of the support L, these rails 40 providing a guideway 41in which the weight moves. The support L comprises uprights 42, a crossbeam 43, braces 44, extending upwardly and diagonally from the frame Bto the beam 43, and tie members 45 connecting beam 43 with an A-frame46, forming a part of the boom hoist E. I

In the example shown, ,the motion transmitting and speed reducingmechanism M is in the form of threepart tackle altho it is to bedistinctly understood that this is merely by way of example, since otherplural-part tackle may be used, or other mechanism associated with thehoisting mechanism and the weight, to move in unison, and so that theweight has less linear movement than the excavating member during ahoisting operation. As shown in Figures 1 and 2, thethree-part tackle isduplicated adjacent opposite ends of the weight, and it suflices todescribe one thereof. In the form shown in Figures 1, 2, 3 and ,4, thethree-part tackle coniprises a multiple sheave block 50 carried bysupportL; a sheave 51 secured to weight K;' and, a cable 52 having itsone end portion secured to and adapted to be wound on the same drum 28,that forms a part of the load hoisting mechanism, and its other endportion secured, as at 53, to a projection 54 of block 55 which supportssheave 51. Thus there is a run 56 of cable, from drum 28 to sheave block50 which may be taken upon the drum 28, on thesame surface thereof.formerly occupied by the cable 35, as the dipper descends; a run 156 ofcable between sheave block 50 and sheave 51; a run 5'? of cable fromsheave 51 back to sheave block 50; and, a run 58 of cable from sheaveblock so to the point of attachment 53 to the Weight. Looking at Figure1, if the drum 28 is rotated counterclockwise the dipper 16 willdescend, and the weight K will. ascend in its guideway 41. However, thelinear movement of the weight Kwill be considerably less than the dipper16, because of this motion transmitting and speed reducingmechanismoperatively connected to the load hoisting mechanism and theweight. The. weight K may be made many times greater than the excavatingmember and its load and in fact may be made sufiiciently heavy tooverbalance the dipper, dipper handle and load, if desired, so as toreduce the horse power required at prime mover 32, during a hoistingoperation, and to facilitate disengagement of the load from the massduring the initial operation of the load collecting and hoistingmechanism for accumulating the load in the dipper. By locating theweight K and support L at the end 11 of frame B, the weight,

assists in maintaining the stability of the excavating machine at theside of the axis of rotation of the frame on its base 8, opposite to theboom D, excavating member F, boom machinery G and those portions of theexcavator hoist H as are to the side of said vertical axis opposite end11.

By overbalancing the dipper, dipper handle and load, as above set out,important advantages are gained. The weight K in the example shown beingmore than three times heavier than the dipper, dipper handle and load,effectively assists in maintaining the stability of the revolving frameB on the carriage A, and the carriage A on the ground. This isespecially advantageous when the boom machinery G and the hoist 1-1 havebeen operated to extend the dipper 16 remote from the.

boom D with the dipper handle 17 substantially horizontal, (as whendumping the load from the dipper) at which time there is a tendency totip the machine in the direction of the dipper if there is notsuflicient counteracting weight adjacent the end 11 of the frame B. Ifthe machine is electrically operated, as by use of the motors 32 and themotor-generator set 34, regeneration during the lowering of the dipperis eliminated, reducing the heating of the hoist motors and generators.In isolated places where the excavating machine must be operated by anelectrical power plant located in the immediate vicinity of theexcavating operations, the power. plant capacity need not be as great aswhere there is equipment which regenerates electricity during thelowering of the dipper and is subjected to extreme peak loads forlifting and causing the. dipper to pene-' trate the mass of material tobe hoisted or moved. According to this embodiment of the presentinvention, the load peak during digging or penetrae tion or" the dipperinto the material to be dislodged and collected is reduced to a minimum.

Assuming that it is desirable to change the position of the boom D, bymoving it upwardly, the dipper and dipper handle remaining in the samerelative position to the boom as shown in Figure 1, he weight K willdescend, since, in order to ..-.ntain this relative position of thedipper handle to the boom, it will be necessary to rotate drum 28, totake up the slack in cable 35. On the other hand, if the boom D is to belowered from the position shown in Figure l, the dipper handle stillretaining its same relative position to the boom, the weight K must belifted, since drum. 28 must be rotated to play out more cable 35 andthis rotation. of the drum lifts the weight through mechanism M. Forthis, and other reasons, the means N is provided for adjusting themotion transmitting and speed reducing mechato change the relativeposition of the weight in its guideway 41, independently of movement ofthe excavating member. This may be accomplished, as shown in Figure 1,by supporting the multiple sheave block so by a screw threaded it 66,extending through an opening 61 in beam 43, the shaft receiving a nut62, or a wheel having an internally screw threaded hub, the shaft 60having a swivel connection with block 50, as shown at 63. The nut 62 mayengage a bearing 64 resting upon beam 43. Thus by rotating nut 62, theplural-part tackle may be bodily moved upwardly or downwardly, accordingto the direction of rotation of the nut, and the relative position ofthe weight K in its guideway changed, While the load hoisting mechanismremains inert. This device may also be used to take up line wear and tomake sure that the weight K is suspended plumb, as hereinbeforedescribed.

If desired the multiple sheave block 50 may be dispensed with, andsingle sheave blocks provided as shown in Figure 5, each independentlysupported by a device N. This permits the blocks 70 to independentlyswivel on the shafts co, for the sheave receiving the run 56 of cable ismost likely to be subjected to wear, as the cable moves on and off thedrum 28, this independent swiveling of the blocks, reducing wear to aminimum.

In the form of invention shown in Figures 6 and 7, the arrangement issimilar to that shown in Figures 1-4, with the exception that the motiontransmitting and speed reducing mechanism M has connection with the loadhoisting mechanism C, at bail 36 of dipper 16, instead of to the drum 28of the excavator hoist E. This makes necessary the use of another boompoint sheave for each run of cable 81 from the bail 36, over the sheave,to the multiple sheave block 50. 'In this example, while the weight Kmay be many times heavier than the dipper 16 and its handle 1'7, so asto assist in maintaining the stability of the excavating machine, itshould not be made so heavy as to overbalance the empty dipper andassociated parts. In this form, if the boom D is raised or lowered, thedipper and its handle still retaining the same relative position to theboom D, the weight K is proportionately lowered or raised, respectively,which emphasizes the importance of means N, otherwise it would benecessary to provide a much longer guideway 41 for the weight.

In the example shown, the invention has been applied to large revolvingshovels, such as are used for coal or ore stripping, that is, forremoving the overburden, or for digging canals, but it is to beunderstood that the invention may be applied to smaller excavatingmachines, and when so doing it may be desirable to support the weight Kby motion transmitting and speed reducing .mechamsm operativelyconnected to the central portion of the weight, instead of duplicatingthis mechanism with connections adjacent opposite ends of the weight.Other means than that comprising the shaft 16 and nut 62 may be utilizedto adjust the weight in its guide-- way, independently of movement ofthe load engaging unit, or this means shown in Figure 4 may be connectedbetween the block 55 and weight K, or the means may be provided at thebeam 43, as well as at the weight, where the boom D is intended forconsiderable movement ina vertical plane. In actual reduction topractice I have found that the application of my invention to excavatingmachines materially increases the capacity of the machine for doingwork, both as to load hoisted, and time required for hoistingoperations. As an example, an excavating machine equipped with two 250H. P. motors to operate the excavator hoistv with a dipper having acapacity of 12 yards, successfully operated a dipper of 18'yardcapacity, after being equipped with my invention. As another example, anexcavating machineyhaving motors of a total of 560 H. P.capacitmformerly using a dipper of 16 yard capacity was equipped withone for 18 yard capacity after application of ing that the conditionsconcurrent with the adoption of the mechanism will necessarily vary, itis desired to emphasize'the fact that various minor changes in detailsof construction, pro-. portion and arrangement of parts may be resortedto, required, without sacrificing any of the advantages of the inventionas defined in the appended claims.

I claim:

1. In an excavating machine, the combination with a frame, and loadhoisting mechanism carried thereby, including, a boom pivotally carriedby the frame, a boom hoist for aising and lowering said boomya loadengaging unit, and a hoist for said load engaging unit including a hoistline having a running connection with the boom remote from thepivotalconnection ofthe.

boom with the frame, of mechanism to counteract the weight of the loadengaging unit, comprising, a weight, a guide for the weight carried.

by the frame, motion transmittingand speed reducing mechanismoperatively connecting a moving part of the load hoisting mechanism andsaid weight to move in unison-so that the Weight has less linearmovement than the load engaging unit during a hoisting operation, andmeans for adjusting said motion transmitting and reducing mechanism tochange the relative position of said weight in its guide, independentlyof movement of the load engaging unit, to compensate for a change inposition of the boom relative to the frame.

2. In an excavating machine, the combination with a frame, and loadhoisting mechanism carried thereby, including, a boom pivotally carriedby the frame, a boom hoist for raising and lowering said boom, a loadengaging unit, and a hoist for load engagin unit including a hoist lnehaving a running connection with the boom.

remote from the pivotal connection of the boom with the of mechanism tocounteract the weight of the load engaging unit, comprising, a weight, asupport carriedby the frame and proa guideway for the Weight,plural-part tackle between the support and weight and sus-- pending theweight in said guideway, said tackle operatively connected to a movingpart of the load hoisting mechanism to move in unison I therewith and sothat the weight has less linear movement than the load engaging unitduring a hoisting oper tion, and means for adjusting the tackle tochange the relative position of the weight its guideway, independentlyof movement the load engaging unit, to compensate for a change inposition of the boom relative to the frame.

3. In an excavating machine, the combination with a frame, and loadhoisting mechanism carried thereby, including, a boom pivotally carriedby the frame, a boom hoist for raising and lowering said boom, a loadengaging unit, and a hoist for said load engaging unit including a hoistline having a running connection with the boom remote from the pivotalconnection of the boom with theframe, of mechanism to counteract theweight of the load engaging unit, comprising, a weight, a supportcarried by the frame and providing a guideway for the weight,plural-part tackle between the support and weight and suspending theweight in said guideway, said tackle operatively connected to a movingpart of the load hoisting mechanism to move in unison therewith and sothat the weight has less linear movement than the load engaging unitduring a hoisting operation, and means for bodily moving the tackle andweight relative to the support.

4. In an'excavating machine, the combination with a frame, a boompivotally carried thereby, a boom hoist for raising and lowering saidboom, a load engaging unit and a hoist for said load engaging unitcarried by the frame and including a hoist line having a runningconnection with the boom remote from the pivotal connection of the boomwith the frame, of mechanism to counteract the weight of the loadengaging unit and its load, comprising, a weight, a guide carried by theframe, motion transmitting and speed reducing mechanism operativelyconnecting a moving part of the load engaging unit hoist and said weightto move in unison so that the weight has less linear movement than theload engaging unit during a hoisting operation, and means for adjustingsaid motion transmitting and speed reducing mechanism to change therelative position of said weight in its guide, independently of movementof the load engaging unit, to compensate for a change in position of theboom relative to the frame.

5. In an excavating machine, the combination with a frame, a boompivotally carried thereby, a boom hoist for raising and lowering saidboom, a load engaging unit, and a hoist for said load engaging unitcarried by the frame and including a hoist line having a runningconnection with the boom remote from the pivotal connection of the boomwith the frame, of mechanism to counteract the weight of the loadengaging unit and its load, comprising, a weight, a support carried bythe frame and providing a guideway for the weight, plural-part tacklebetween the support and weight and suspending the weight in saidguideway, said tackle operatively connected to a moving part of the loadengaging unit hoist to move in unison therewith and so that the Weighthas less linear movement than the load engaging unit during a hoistingoperation, and means for adjusting the tackle to change the loo relativeposition of the weight in its guideway, in-

dependently of movement of the load engagingunit, to compensate forachange in position of the boom relative to the frame.

6. In an excavating machine, the combination with a frame, a boompivotally carried thereby, a boom hoist for raising and lowering saidboom, a

load engaging unit, and a hoist for said load enand weight andsuspending the weight in said guideway, said tackle operativelyconnected to a moving part of the load'engaging unit hoist to move inunison therewith and so that the weight has less linear movement thanthe load engaging unit during a hoisting operation, and means for bodilymoving the tackle and weight relative to the support.

'7. In an excavating machine, the combination with a frame, and loadhoisting mechanism carried thereby including a load engaging excavatingmember, of mechanism to counteract the weight of the said membercomprising a support providing a vertical guideway, a weight movable insaid guideway, motion transmitting and speed reducing mechanismoperatively connecting a moving part of said load hoisting mechanism andsaid weight to move in unison so that the weight has less linearmovement than the load engaging and

